MMI 1053 EXAM #4

Antigens are best defined as:

Substances that generate an immune response

A pediatric patient is brought to the emergency department with a high fever of 102.5°F, which was not reduced after giving acetaminophen. What is an appropriate statement to the parents?

All of these statements are appropriate for this situation

___________ is lifelong immunity to infection by a pathogen following recovery from an initial exposure.

Natural active immunity

Katie is breastfeeding her one day old infant which allows her to share her antibodies with her baby. This is an example of

natural, passive immunity.

T cell maturation occurs in the ____________________.

thymus

All circulating blood cells are produced by ___________ which occurs in the _______.

hematopoiesis; bone marrow

The correct sequence of steps involved in the inflammatory response is ________.

1. diapedesis of leukocytes out of capillaries and into surrounding tissues

2. enhanced blood flow to injured area with subsequent development of heat and redness

3. release of inflammatory mediators from a variety of sources triggering vasodilation

4. plasma leaves blood vessels brining various agents of help to damaged tissue

5. macrophages and lymphocytes get rid of pus and cellular debris, and homeostasis is reestablished

6. increased fluid in tissues leads to edema, pain and phagocytosis of invading pathogens

3, 2, 1, 4, 6, 5

The correct sequence of events in the action of interferon is ________________.

1. Viral infection of host cells causing rapid production and secretion of Type I IFNs

2. Host cell produces antiviral proteins that can degrade viral RNA, inhibit protein synthesis and virion assembly and prevent viral gene expression

3. Modification of neighboring cell's gene expression induces an antiviral state

4. Binding of IFNs to receptors on uninfected neighboring cells

1, 4, 3, 2

Adaptive immunity is mediated by _____ and _____, which demonstrate _____ and _____.

B lymphocytes; T lymphocytes; specificity; memory

The diagram illustrates the structure of

IgM.

_______ is the antibody class found in tears, colostrum, saliva and mucus.

IgA

___________ refers to antibody binding to pathogens and toxins, blocking their attachment to host cell receptors.

Neutralization

___________ triggers microbial lysis and enhances inflammation.

Complement activation

On an antibody molecule, the region that shows the highest affinity for antigen binding is the

variable region.

T cells that eliminate intracellular infections are

cytotoxic T cells.

Cells that attack self-antigens

are eliminated during lymphocyte development.

_______ is the antibody class that crosses the placenta to provide passive immunity to neonates.

IgG.

The specific portion of a macromolecular antigen that binds a lymphocyte receptor and triggers an adaptive immune response is a(n) _____________.

epitope

What cells recognize grafted foreign tissue (e.g., heart) and begin the process of rejection?

cytotoxic T cells

Which type of vaccine would NOT be given to an immunocompromised patient?

live attenuated vaccine

This vaccine requires a booster at regular intervals in order to maintain maximum effectiveness.

Tetanus

Autoimmune diseases are the result of attacks on

self-antigens.

How did Edward Jenner provide artificially acquired active immunity against smallpox?

He inoculated patients by scratching them with a needle covered in the fluid from cowpox blisters.

______________ vaccines contain attenuated toxins and require regular boosters.

Toxoid

How does vaccination stimulate immunity?

induces artificially acquired active immunity

______________ vaccines contain attenuated pathogens incapable of reproducing so multiple doses are required and they are safe for immunocompromised patients.

Inactivated

__________ is the inadvertent protection of unimmunized individuals because most of the population is immunized so the pathogen lacks a reservoir.

Herd immunity

Patients with SCID may be successfully treated with ________.

a bone marrow transplant

_____________ is an autoimmune disease that attacks the myelin sheath.

Multiple sclerosis

ABO blood typing is determined by performing a ______ test.

direct agglutination

The so-called "ciliary escalator" functions by...

Moving microbes towards the throat

Which of the following steps of the inflammatory response is the main cause of the associated redness?

Vasodilation

Which of the following statements is an accurate description of the innate immune system?

All of the above are accurate descriptions of the innate immune system

Which class of antibody has the most antigen binding sites and is therefore the most useful in containing an initial microbial infection?

IgM

In a cell mediated immune response, which cell type is assisting in the activation of the B cells to produce antibodies?

Helper T cells

A person injected with a toxoid, such as tetanus toxoid, will develop which type of immunity?

Artificially acquired, active immunity

With which of these vaccines is the antigen which triggers the immune response actually made by the host?

mRNA vaccine

Which of the following descriptions of herd immunity is correct?

All of the above statements are correct

Which of the following is NOT a scientifically proven problem with vaccination?

Vaccines cause autism

When clonal selection and expansion of B cells occurs in a lymph node

All of the above statements are correct

How does the infection of a weakened form of a viral pathogen provide long term immunity in a patient?

The weakened form once rejected activates the immune system and generates memory cells

While the immune system protects us against invading pathogens, there are some undesirable potential consequences to its actions. These include all of the following EXCEPT

inflammatory responses to breaching of the skin like cuts and scrapes

How many different classes of antibody are found in the human body?

fve

What is not a first line defense mechanism against pathogens?

phagocytosis

Which part of an antibody actually binds to an antigen?

variable region of the light chain at the amino terminus

Describe how innate immunity protects us against infection

nonspecific, immediate, consistent

In relation to innate immunity, a low grade fever can be beneficial because

it stimulates the production of interferon to fight viruses, increases the number of leukocytes being produced, slows bacterial pathogen growth

You slice open your hand working in your yard and go to an urgent care clinic. After stitching the wound, they give you antiserum to protect you from tetanus. What type of immunity do you acquire?

artificially acquired passive immunity

What is not a desired quality for a successful modern vaccine?

short-lived memory response

Which type of WBC is most active against virus infected host cells and non-self, implanted tissues?

cytotoxic T cells

The SARS-CoV2 vaccines produced in the past year by Pfizer and Moderna are what type of vaccine?

mRNA vaccine

Which structure present on some bacteria and fungi acts like an "invisibility cloak" and protects them from phagocytosis?

capsule

All of the following are steps in the inflammatory process. Which is the second step

vasoconstriction

How do normal microbiota provide protection from infection?

produce antibacterial chemicals, compete with pathogens for nutrients, make chemical environment unsuitable, change pH of the environment

What type of immunity results form recovery from mumps?

naturally acquired active immunity

Virus infected cells secrete which molecule(s) to warn and fortify neighboring cells against impending viral attack?

interferons

Which type of vaccine show NOT be given to immunocompromised patients?

live attenuated vaccine

What is a true statement about the complementary system?

there are more than thirty complement proteins

The most abundant class of antibodies in serum is

IgG

In which organ of the body do T lymphocytes mature

thymus

Macrophages with defective lysosomes are unable to

kill ingested microbes

When ana antibody binds to a toxin, preventing it from working, the resulting action is referred to as

neutralization

Which class of antibodies is typically found in mothers milk, saliva, and tears?

IgA

The terms "herd immunity" , "free riders", and "threshold" are defined as

Al of these statements are correct

Antigens are best defined as

substances that generate an immune response

The short-lived plasma cells that secrete antibodies are produced by the activation and expansion of which type of cells?

B cells

In a "cell-mediated" secondary immune response, which type of cell is assisting or "mediating" the antibody response?

T cells

What type of immunity results form vaccination?

artifically acquired active immunity

What is NOT a characteristic of inflammation?

stiffness of joints

Which vaccine, at a very low frequency, is able to revert to virulence and cause the disease it is designed to prevent?

oral polio vaccine